A CRISPR/Cas12 trans-cleavage reporter enabling label-free colorimetric detection of SARS-CoV-2 and its variants.
Biosens Bioelectron
; 251: 116102, 2024 May 01.
Article
in En
| MEDLINE
| ID: mdl-38350240
ABSTRACT
We present a label-free colorimetric CRISPR/Cas-based method enabling affordable molecular diagnostics for SARS-CoV-2. This technique utilizes 3,3'-diethylthiadicarbocyanine iodide (DISC2(5)) which exhibits a distinct color transition from purple to blue when it forms dimers by inserting into the duplex of the thymidine adenine (TA) repeat sequence. Loop-mediated isothermal amplification (LAMP) or recombinase polymerase amplification (RPA) was used to amplify target samples, which were subsequently subjected to the CRISPR/Cas12a system. The target amplicons would activate Cas12a to degrade nearby TA repeat sequences, preserving DISC2(5) in its free form to display purple as opposed to blue in the absence of the target. Based on this design approach, SARS-CoV-2 RNA was colorimetrically detected very sensitively down to 2 copies/µL, and delta and omicron variants of SARS-CoV-2 were also successfully identified. The practical diagnostic utility of this method was further validated by reliably identifying 179 clinical samples including 20 variant samples with 100% clinical sensitivity and specificity. This technique has the potential to become a promising CRISPR-based colorimetric platform for molecular diagnostics of a wide range of target pathogens.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Biosensing Techniques
/
COVID-19
Type of study:
Diagnostic_studies
Limits:
Humans
Language:
En
Journal:
Biosens Bioelectron
Journal subject:
BIOTECNOLOGIA
Year:
2024
Document type:
Article